Manufacture of bags



Jan. 5, 1937. J, M. DRIVER MANUFACTURE OF BAGS -,m. mlm

Filed May 14, 1935 Patented Jan. 5, 1,937

PATE

Erica MANUFACTURE F BAGS.

John M. Driver, San Franciscol C.

Application May 1i,

This application relates to the same subject matter' as myapplication Serial No. 634,751, nled Sept. 24, 1932, Patent No. 1,997,378, Apr. 9, 1935.

My invention relates to the manufacture of bags and other containers of thin paper or similar webs of other cellulosic material and more particularly to the manufacture of bags and similar containers from the thin lm or pellicle familiarly known as Cellophane.

One object of my invention is to facilitate the handling of thin webs or pelllcles of paper or cellulosic material, notably Cellophane, when employed in the manufacture of bags and other containers and wherein the necessary manipulation requires that the web or pellicle be cut, slit or otherwise ruptured to effect formation of the desiredA article.

A further object of my invention is to facilitate the formation of bottoms of the satchel type in the manufacture of bags or similar containers from thin paper or other material, particularly Cellophane. The formation of bottoms of the satchel type requires that the wall ofthe tube vfrom which these bags or other containers are made shall be slit lengthwise of the same in order that, in the finally folded form of such bottoms. the overlapping tabs which will be presented by reason of cutting or slitting the tube may be secured in place by pasting or otherwise to complete such bottoms without danger of tearing the material. In the formation of isolated cuts or slits in the body of thin material, especially material.

such as Cellophane, which is without nbre and under certain conditions is liable to readily tear and will tear following such cuts or slits. it is necessary that some provision be made for preventing a continuation of these cuts or slits since a con-- tinuation of the same would seriously damage the bag bottom, prevent its formation in many instances, and utterly destroy its function.

'I'he main object of my invention is to provide means in thepreparation of the material for bag making whereby these isolated slits or cuts will not extend beyond the dimensions of the same initially intended.

These and other features of my invention are more fully set forth hereinafter; reference being had to the accompanying drawing, more or less diagrammatic in character, in which:

Fig. 1 is a plan view of a section of web from which bags and similar containers may be made in accordance with my invention.

Fig. 2 is a plan view of a tube formed from a web of the character shown in Fig. 1.

1935, Serial No. 21,396

Fig. 3 is a cross-sectional view of the tube on line III-III, Fig. 2.

Fig. 4 is a diagrammatic view illustrating certain of the steps of bag formation, and

Fig. 5 is a plan view of a finished bag of the 5 satchel bottom type.

In the manufacture of many types of bags and similar containers from paper and the like, a web is unwoundfrom a reel, passed to tube-forming mechanism, hence to blank-severing means, and thence to bottoming mechanism. In the manufacture'of a great many types of bags, it is desirable to effect the formation of a square bottom or a bottom of the satchel type, and in both instances it is necessary to slit or cut the walls of l5 the tube-at isolated points for the purpose of developing tabs which are overlapped and pasted down in the nal formation of such bottoms.

In carrying out my invention; I propose to make bags of Ce1lophane" with satchel or square 20 bottoms The clean-cut edges of Cellophane" resist a. tearing action to a marked degree. 'Ihe slits employed in preparing the bag blanks for the formation of satchel or square bottoms, however, break through the body of the material and it can be well understood, therefore, that if plain slits or cuts are provided in the body of a tube made from a web of Cellophane, the manipulation of the end oi the tube blank where such slits would appear, in the formation of the bottom, would result in a continuation of such slits throughout the portion intended for the bottom and extend to the sides and preclude the possibility of the development of a proper bottom.

Ipropose to overcome this diiiiculty by arranging the slits or cuts in such position that one terminal of the same longitudinally of the blank will be at the open end of the bag being formed, while the other terminal meets a preformed aperv ture cleanly cut through the walls of the body of "Cellophane; thereby preventing extension of the slit beyond the clean-cut edge of the aperture into which one end of such slit opens.

In Fig. l, the web is indicated at A, with a series of apertures a and a formed therein at 15` bag-length intervals. It will be understood, of course, that the view is entirely diagrammatic and that the width ofthe web indicated is purely relative, for illustrative purposes only, and that the bag-length intervals may be changed as desired.

Fig. 2 shows the web in tube formation, the I apertures a, adjacent the margins, registering with the apertures a', which are disposed cenmuy er the web. After the web has been formed into a tube, which is done by suitable and well known tube-forming mechanism, it is passed to slitting or cutting mechanism; the slits indicated at b being relatively of the length indicated with reference to the apertures which -they meet at wall of the bag blank and a recess c' at the adjacent end of the preceding blank which serves as a notch at the open end of the bag produced therefrom facilitating opening of the same when Dutinblt if this point, the bags are presented to fbottoming mechanism oi the usual type employed in the formation of satchel or square bottoms and which, in the case of satchel botther into the body of the web.

toms. may prepare a bottom of the type indicatedvin Fig. 5,' wherein the tabs, produced by the longitudinally arranged slits or cuts b and the transverse cuts on the line a: which sever the blank into bag lengths, are shown in overlying position centrally of such bottom. It willbe noted' that the side edges of such tabs are produced by the slits or cuts b and that such slits or cuts terminate in the preformed apertures and .prevented thereby from extending fur- While I prefer thatv the preformed ape vshall becircular inc0nt0ur,itwi1lbe linderstood that apertures of other shapes are within the scope of my invention, provided auch apertures have clean-cut edges. In all instances, the

osano apertures will be so ,the slit-forming implements in through positioned in the tube that the walls oi the tube will Just" enter such apertures so as to insure that there will be no breaking of the clean-cut edge of the same beyond the slit.

While I have referred particularly to the manufacture of bags and other similar containers from thin webs or pellicles and particularly from the material known as Cellophane", it is within the purview of my invention to employ the preformed aperturesin connection with isolated v slits or cuts made in the body of such webs whether the latter are subsequently formed into tubes for the production of bag blanks, made into bags or similar wrappers or other containers, or made into envelopes, and/or the like.

Having thus described this invention, what I claim and desire to secure by Letters Patent is:

l. Asia new article of manufacture, a bag of thin cellulosic material having a bottom including overlapping tabs disposed centrally of such bag bottom and secured together; said tabs having clean-cut side edges produced by slitting the web and such slits terminating in openings with clean-cut marginal edges, the holes through op-I posite webs of the bag being in registry when said webs are slitted to form the tabs preparatory to forming the bag bottom. v

2. As a new article of manufacture, a bag of "Cellophane" having a bottom including overlapping tabs disposed centrally of such bag bottom and secured together; said tabs havins clean-cut side edges produced by slitting the web and such slits terminating in. openings with i JonN u. Druvna. 

